Image data transmission apparatus and method, remote display control apparatus and control method thereof, program, and storage medium

ABSTRACT

In a case where a display screen of a transmission originator, including image data such as photographs, is displayed remotely on a device of a transmission destination, compressed image data of the image portion such as photographs on the display screen which is stored in a storage unit of the transmission originator is transmitted to the transmission destination device so that the image of the photograph portion can be displayed remotely on the screen of the transmission destination device with high image quality.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a technique of displaying an image,which is displayed on a display unit of a portable device, on a displayunit of an apparatus connected to the portable device through a networkwith high image quality.

2. Description of the Related Art

Still images and moving images captured by an image capturing apparatus,e.g., a digital camera and a video camera, can be displayed on a screenof a television apparatus connected to the image capturing apparatuswith a cable or the like so that a plurality of users can view theimages simultaneously. More specifically, image signals displayed on ascreen of an image capturing apparatus are converted to a televisionimage according to the NTSC (National Television System Committee)method. The NTSC image is outputted to a television apparatus connectedto the image capturing apparatus with a cable, thereby achieving thedisplay.

The display format of a television apparatus includes the NTSC methodwhere displaying is realized with 720×480 resolution, and the HD methodwhere displaying is realized with 1920×1600 high resolution.

In a network-connected environment, there is a remote desktop techniquethat enables a client machine to remotely operate a server machine. Thedesktop screen of a server machine is converted to a bitmap image, andthe converted bitmap image is sequentially transmitted to a clientmachine which performs the remote operation according to a predeterminedprotocol. The transmitted bitmap image is enlarged or reduced to adaptthe size to the screen of the client machine. This realizes remotedisplaying of the desktop screen of the server machine.

The above-described conventional art is disclosed in, e.g., JapanesePatent Application Laid-Open No. 6-124080.

However, in a conventional portable device such as a digital camera, ina case of generating a low-resolution image such as an NTSC image on thedisplay screen and transmitting the image to a large-size televisionapparatus to be displayed, there is a problem of significant coarsenessof the image.

SUMMARY OF THE INVENTION

The present invention has been proposed in view of the above-describedproblem, and has as its object to provide a technique of displaying animage, which is displayed on a display unit of a portable device such asa digital camera, on a display unit of an apparatus connected to theportable device through a network with high image quality.

To solve the above problems and achieve the above object, according tothe present invention, an image data transmission apparatus thattransmits image data corresponding to a display of a display unit to adevice connected to the apparatus through a network for having thedevice display the display of the display unit, comprising:

a transmission data generation unit that generates transmission dataincluding image data corresponding to the display of the display unitand attribute information of the image data; and

a transmission control unit that transmits the transmission datagenerated by the transmission data generation unit to the deviceconnected to the apparatus through the network.

According to the present invention, it is possible to display an image,which is displayed on a display unit of a portable device, on a displayunit of an apparatus connected to the portable device through a networkwith high image quality.

Further features of the present invention will become apparent from thefollowing description of exemplary embodiments with reference to theattached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of the specification, illustrate embodiments of the invention and,together with the description, serve to explain the principles of theinvention.

FIG. 1 is an overview of a system including a television apparatus, adigital camera and the like according to an embodiment of the presentinvention;

FIG. 2A is a block diagram showing a configuration of a digital camera(first device) according to the embodiment of the present invention;

FIG. 2B is a block diagram showing a configuration of a remote displaycontrol apparatus according to the embodiment of the present invention;

FIG. 3 is a block diagram showing as an example a configuration of atelevision apparatus (second device) according to the embodiment of thepresent invention;

FIG. 4 shows as an example a piece of compressed image data captured bya digital camera 103 and displayed on a display unit 207 with anadjusted aspect ratio to adapt the size to the display unit 207;

FIG. 5 is a flowchart describing the processing for transmittingcompressed image data, which is corresponding to a piece of imagedisplayed on a display unit of a digital camera, to a televisionapparatus connected to the digital camera through a network;

FIG. 6 is a flowchart describing the processing for receiving datatransmitted by a digital camera and displaying it on a display unit of atelevision apparatus;

FIG. 7 shows an example where a display screen of a digital cameradisplaying a piece of image data is remotely displayed on a display unitof a television apparatus;

FIG. 8 shows an example where captured images are displayed in order offile names;

FIG. 9 is a view showing a data structure used in thumbnail displayingin FIG. 8;

FIG. 10 shows an example of rendering data in the SVG (Scalable VectorGraphics) format written in a structured document data, which is usedfor rendering on a display unit of a digital camera;

FIG. 11 is a flowchart describing the processing for displaying pluralimage data on a display unit of a digital camera based on a backgroundimage, captured compressed image data, and rendering data;

FIG. 12 shows an example of a transmission data structure in the XOP(XML-binary Optimization Packaging) format; and

FIG. 13 shows an example where a screen of a digital camera displayingplural image data is remotely displayed on a display unit of atelevision apparatus.

DESCRIPTION OF THE EMBODIMENTS

Preferred embodiments of the present invention will now be described indetail in accordance with the accompanying drawings. FIG. 1 is anoverview of a system including a television apparatus 101, a digitalcamera 103 and the like according to an embodiment of the presentinvention. In FIG. 1, the television apparatus 101 is connected to theLAN 102. Connected to the LAN 102 are: an image data transmissionapparatus 103 (hereinafter a digital camera will be explained as apreferred example) such as a digital camera or a mobile telephone havinga camera function and so forth, a data processing apparatus (PC) 104,and a file server 105.

FIG. 2A is a block diagram showing a configuration of the digital camera(first device) 103, which serves as an image capturing apparatusaccording to the embodiment of the present invention. In FIG. 2A, theCPU 201 serving as a system controller controls the entire digitalcamera 103. ROM 202 is provided for storing various fixed data andcontrol programs of the CPU 201. RAM 203, configured with SRAM, DRAM orthe like, is provided for storing program control variables and soforth. Various setting parameters and various work buffers are alsostored in the RAM 203. A storage unit 204, configured with a hard diskor the like, is provided for storing captured image data. Aphotographing unit 205 is configured with an image capturing elementwhich captures a photograph target, e.g., landscape and portrait. Anoperation unit 206, configured with buttons, a touch panel and so on, isprovided for an operator to perform various input operations. A displayunit 207 is configured with an LCD or the like. A LAN I/F 208 is aninterface for connection with a LAN line 209. A USB I/F 210 is aninterface for connection with a USB line 211. Image data captured by thedigital camera 103 can be stored in the file server 105 together with ananalysis result of its attribute.

The digital camera (image data transmission apparatus) 103 according tothe present embodiment comprises a transmission data generation unit 212for generating, under the control of the CPU 201, transmission data thatincludes compressed image data corresponding to the display of thedisplay unit 207 and attribute information of the compressed image data.The digital camera (image data transmission apparatus) 103 alsocomprises a transmission controller 213 for transmitting, under thecontrol of the CPU 201, the transmission data generated by thetransmission data generation unit 212 to a device connected through thenetwork 102. The transmission controller 213 is capable of transmittingthe generated transmission data to the designated device in a HTTP(Hyper Text Transfer Protocol) format according to a user's transmissiondesignation. The transmission controller 213 is also capable oftransmitting data in a TCP/IP format.

In a case where the displaying on the display unit 207 is performedbased on a plurality of image data, the transmission data generationunit 212 adds attribute information, which indicates that thetransmission data is in a XOP (XML-binary Optimization Packaging)format, to the header of the transmission data. The XOP format will bedescribed later with reference to reception processing of plural imagedata.

In a case where the displaying on the display unit 207 is performedbased on a plurality of image data such as that shown in FIG. 9, thetransmission data generation unit 212 generates transmission data basedon a background image 901 and rendering data 903 stored in the RAM 203as well as compressed image data 902 in the storage unit 204. Therendering data 903 includes reference information (data names and ID)specifying each compressed image data and background image data, andlayout information specifying the display size and position based oneach compressed image data and background image data on the display unit207.

The specific processing of the above description corresponds to FIG. 9,FIG. 10, and step S306 in FIG. 11.

A remote display control apparatus 280 adapts the display of the displayunit 207 of the first device (digital camera 103) to the display formatof the display unit 305 of the second device (television apparatus 101or PC 104). The remote display control apparatus 280 has a configurationshown in FIG. 2B.

In FIG. 2B, ROM 252 is provided for storing various data and controlprograms of a CPU 251. RAM 253, configured with SRAM, DRAM or the like,serves as an internal memory for storing program control variables andso forth. A storage unit 254, configured with a hard disk or the like,is capable of storing compressed image data, attribute informationindicative of an attribute of the compressed image data and so on, whichare transmitted from the digital camera 103.

An analysis unit 271 analyzes an attribute of compressed image dataincluded in the transmission data transmitted from the first device(digital camera 103). In accordance with an analysis result of theanalysis unit 271, an image data generation unit 273 generates imagedata, which is adapted to a display format of the display unit 305 ofthe second device, based on the compressed image data transmitted fromthe digital camera 103. Based on the generated image data, a displaycontrol unit 274 displays the image data on a display unit 305 of thesecond device (e.g., television apparatus 101).

FIG. 3 is a block diagram showing as an example a configuration of thetelevision apparatus (second device) 101 according to the embodiment ofthe present invention. In FIG. 3, a CPU 301 serving as a systemcontroller controls the entire apparatus. ROM 302 is provided forstoring various fixed data and control programs of the CPU 301. RAM 303,configured with SRAM, DRAM or the like, is provided for storing programcontrol variables and so forth. Various setting parameters and variouswork buffers are also stored in the RAM 303. An operation unit 304,configured with buttons, a touch panel and so on, is provided for anoperator to perform various input operations. A display unit 305 is atelevision screen for displaying an image. A LAN I/F 306 is an interfacefor connection with a LAN line 307. A USB I/F 308 is an interface forconnection with a USB line 309. Through the LAN I/F 306 or the USB I/F308, the television apparatus 101 is capable of receiving datatransmitted by the digital camera 103.

In FIG. 3, numeral 280 denotes the remote display control apparatusdescribed in FIG. 2B. By virtue of the apparatus 280, it is possible toadapt the display of the display unit 207 of the digital camera 103 tothe display format of the display unit 305 of the television apparatus101, thus realizing high-quality image displaying. Note that FIG. 3shows an example where the remote display control apparatus 280 isincorporated in the construction of the television apparatus 101.However, also in a case of controlling the display of the PC 104, theremote display control apparatus 280 may be incorporated in theconstruction of the PC 104 for enabling the display control adapted tothe display format of the display unit of the PC 104.

Example on Remote Displaying

Described next is an example where a piece of image compressed in theJPEG format, which is displayed on the display unit 207 of the digitalcamera 103, is remotely displayed on a screen of the televisionapparatus 101 or PC 104. The compressed image data in the JPEG format isstored in the storage unit 204. By referring to the stored data, the CPU201 can display the image on the display unit 207.

Note that although the present embodiment describes the JPEG (JointPhotographic Experts Group) format data as an example of compressedimage data, the purport of the present invention is not limited to this,and the invention is applicable to data compressed in the PNG (PortableNetwork Graphics) format.

FIG. 4 shows an example of a display screen where an image captured bythe digital camera 103 is displayed on the display unit 207 of thedigital camera 103. The display screen of the display unit 207 has animage selection button 401 and a send button 402 for designatingtransmission of the compressed image data which corresponds to theselected image.

By operating the image selection button 401, a user can switch imagesdisplayed on the display unit 207 in sequence. The user selects adesired image and depresses the send button 402. When this operation isdetected, the digital camera 103 generates transmission data regardingthe selected image, and shifts the control to transmission processing ofthe generated transmission data. Hereinafter, data transmissionprocessing is described with reference to the flowchart in FIG. 5.

Data Transmission Processing

FIG. 5 is a flowchart describing the processing for transmitting underthe control of the CPU 201 compressed image data, which is correspondingto a piece of image displayed on the display unit 207 of the digitalcamera 103, to the television apparatus connected to the digital camera103 through the network.

First, mode selection for displaying a piece of image on the displayunit 207 is detected (S102). Then, a file name of compressed image data,corresponding to the image selected by the user on this mode, is storedin an internal memory (e.g., RAM 203) (S103).

With reference to the size of the area of the display unit 207 where theimage is to be displayed, the CPU 201 performs thinning of the imagedata and generates image data to be displayed on the display unit 207(S104).

In step S105, the CPU 201 determines whether or not the user hasselected the send button 402. If it is determined that the send button402 has been selected, the transmission data generation unit 212 refersto the file name stored in the internal memory and selects thecompressed image data and attribute information indicative of theattribute of the compressed image data which are stored in the storageunit 204 as a substitute image data of the image data displayed on thedisplay unit 207. Based on the selected compressed image data andattribute information, transmission data is generated. The transmissiondata generation unit 212 determines an attribute of the compressed imagedata. In a case where the compressed image data is in the JPEG format,attribute information “image/jpeg” is added to the header of thetransmission data to generate transmission data. Under the control ofthe CPU 201, the transmission controller 213 transmits the generatedtransmission data to an apparatus connected through the network 102(e.g., the television apparatus 101) in the HTTP format (S106).

Data Reception Processing

Described next is reception processing of the television apparatus 101which receives the transmission data transmitted by the digital camera103.

FIG. 6 is a flowchart describing the processing for receiving thetransmission data transmitted by the digital camera 103 and displayingit on the display unit 305 of the television apparatus 101. The CPU 301monitors data transmitted in the HTTP format from other devices,including the digital camera 103, through the LAN I/F or USB I/F (306 or308) (S202). When the CPU 301 determines that data in the HTTP format isreceived, the CPU 301 returns a result, indicative of the successfuldata reception, to the digital camera 103 which is the originator of thetransmission data (S204).

In step S205, the attribute information added to the header of thetransmission data in the HTTP format, which is transmitted from thedigital camera 103, is analyzed. In step S206, it is determined whetheror not the attribute information is a JPEG format. Herein assume thatthe determination processing on attributes is performed by the analysisunit 271 of the remote display control apparatus 280 under the controlof the CPU 301.

In a case where the analysis result of the attribute information of thecompressed image data is JPEG format (YES in S206), the control proceedsto step S207 where the compressed image data is analyzed and a bitmapimage is generated.

In step S214, based on the generated bitmap image, a raster image in theNTSC format, HD format or the like that is adapted to the display formatof the display unit 305 is generated and displayed on the display unit305 (S214). Herein, assume that the generation processing of the rasterimage adapted to the display format of the display unit 305 is performedby the image data generation unit 273 under the control of the CPU 301,and that displaying of the image on the display unit 305 is performed bythe display control unit 274.

According to the above-described processing, a piece of image displayedon the display unit 207 of the digital camera 103 can be displayed onthe display unit 305 of the television apparatus 101 with high imagequality as shown in FIG. 7.

When the user designates selection and transmission of a next image withthe use of the operation button 401 and the send button 402 of thedigital camera 103, transmission data that includes compressed imagedata corresponding to the selected image is newly generated according tothe similar procedure. The newly generated transmission data isprocessed by the analysis unit 271, the image data generation unit 273,and the display control unit 274, and a raster image adapted to thedisplay format of the display unit 305 is generated. As a result, highquality image displaying becomes possible.

Remote Displaying of Plural Images

Described next is an example of remote displaying of plural capturedimages, which are displayed on the display unit 207 of the digitalcamera 103, on the screen of the television apparatus 101. FIG. 8 showsan example where captured images pic001.jpg to pic006.jpg are displayedin order of image file names. On the background (back.bmp) of theseimages, frames for arranging the images as well as “display”, “delete”,and “send” buttons 801 are provided for an operator to operate. When abutton is operated on the touch panel provided on the display unit 207of the digital camera, an event (instruction) is informed to theapplication program, thereby enabling to switch the thumbnail images.

FIG. 9 is a view showing a data structure used in thumbnail displayingin FIG. 8. Assume that the background image 901 written with bitmap dataand the rendering data 903 in the Scalable Vector Graphics (SVG) format,which is used in displaying the background image 901 and captured imagedata on the display unit of a digital camera, are stored in the RAM 203.Further assume that the compressed image data 902 which has beencaptured is stored in the storage unit 204.

Assume that the rendering data 903 is a structured document data in theSVG format based upon the vector graphics specification of the W3C(World Wide Web Consortium) standard as shown in FIG. 10. In therendering data 903, the background image 901 (data name: ‘back.bmp') isallocated to ID=0. Further, the display position of the background image901 is designated to be rendered with the top left coordinates (0, 0),the width of 400 pixels, and the height of 350 pixels.

In FIG. 10, the data name and ID, which are the reference information,specify each compressed image data (including the background image).Information related to the top left coordinates, width, and height,which are the layout information, specify the display position and sizeof each compressed image data (including the background image) on thedisplay unit 207. By virtue of the rendering data 903, each compressedimage data (including the background image) can be associated with thelayout information.

In the example shown in FIG. 10, IDs 1 to 6 are allocated to compressedimage data (data names: pic001.jpg to pic006.jpg) as referenceinformation. For layout information, the top left coordinates (X, Y),width and height data with which each image data is to be rendered onthe screen are designated.

The rendering data 903 in the SVG format includes reference informationand layout information related to each compressed image data. Changingthe description of the layout information in the rendering data 903 cancontrol the display position and size of each compressed image data onthe television apparatus 101.

Data Transmission Processing

A description is provided on the processing for a case where imagesbased on plural image data are displayed on the display unit 207 of thedigital camera 103. FIG. 11 is a flowchart describing the processing fordisplaying plural image data on the display unit 207 of the digitalcamera 103 based on the background image 901, captured compressed imagedata 902, and rendering data 903 under the control of the CPU 201.

First, user's mode selection for displaying plural images is detected(S302) In response to detection of the mode selection, the CPU 201generates a rendering image by analyzing the rendering data 903 storedin the RAM 203 (S303). Then the generated rendering image is displayedon the display unit 207 (S304). In step S305, the CPU 201 determineswhether or not selection of the send button 801 has been detected.

When selection of the send button 801 is detected, the transmission datageneration unit 212 generates transmission data shown in FIG. 12 basedon the background image 901 and rendering data 903 in the RAM 203 aswell as the compressed image data 902 in the storage unit 204 under thecontrol of the CPU 201 (S306).

Attribute information 1201 (‘multipart/related’) indicating that thetransmission data bases upon the plural image data displayed on thedisplay unit 207 is added to the header of the transmission data, whichhas been generated by the transmission data generation unit 212 underthe control of the CPU 201. The transmission data further includes theaforementioned reference information (ID 1202, data name 1203), layoutinformation (top left coordinates, width, and height of the screen)1204, and each compressed image data 1205.

The transmission data is in the XOP format publicized as a W3Crecommendation, which is a specification providing the standard means topacket an XML document and binary data as it is into a communicationpacket for handling binary data in a Web service. The analysis unit 271of the remote display control apparatus 280 can determine whether or notthe transmission data is in the XOP format based on the attributeinformation 1201 (‘multipart/related’).

In step S307, the transmission controller 213 transmits the generatedtransmission data to the apparatus (e.g., television apparatus 101)connected through the network 102 in the HTTP format under the controlof the CPU 201.

Data Reception Processing

When the television apparatus 101 receives the transmission data in theXOP format that has been transmitted in the HTTP format from the digitalcamera 103, the transmission data is processed according to steps S202to S205 in FIG. 6 as similar to the processing of compressed image datacorresponding to a piece of image.

When the analysis in step S206 finds that the attribute informationadded to the header of the transmission data is not JPEG-format(image/jpeg) data (NO in S206), the control proceeds to step S208.

In step S208, the analysis unit 271 of the remote display controlapparatus 280 determines whether or not the attribute information addedto the transmission data is XOP format (multipart/related) data underthe control of the CPU 301. If the analysis unit 271 determines that thetransmission data is not XOP format data (NO in S208), the CPU 301returns information back to the digital camera 103, which is thetransmission originator, that the transmission data is not supported bythe television apparatus 101 (S215)

Meanwhile, if the analysis in step S208 determines that the transmissiondata is XOP format data (YES in S208), the analysis unit 271 furtheranalyzes the transmission data (S209). Then, the analysis unit 271stores rendering data in the SVG format in the internal memory (S210),and then stores binary data of the compressed image included in thetransmission data as well as the corresponding data name in the internalmemory (S211).

In step S212, based on the display method of the television apparatus101 such as the NTSC method and HD method, the image data generationunit 273 obtains a scaling factor necessary to display each compressedimage data on the television screen. The image data generation unit 273rewrites the rendering data (reference information and layoutinformation) in the SVG format stored in the internal memory based onthe obtained scaling factor to be adapted to the display method of thedisplay unit 305, and stores it in the storage unit 254 (S212). Byvirtue of the processing in step S212, it becomes unnecessary to referto the display method of the television apparatus 101 each time imagedata is re-rendered; as a result, rendering speed increases. The imagedata generation unit 273 generates image data rendered based on therewritten rendering data in the SVG format (S213).

In step S214, the image data generation unit 273 generates a rasterimage based on the generated image data according to the display formatof the display unit 305 of the television apparatus 101. The displaycontrol unit 274 of the remote display control apparatus 280 causes thedisplay unit 305 of the television apparatus 101 to display the rasterimage generated by the image data generation unit 273 (S214).

As a result, for instance, the images displayed on the display unit 207of the digital camera 103 can be displayed on the display unit 305 ofthe television apparatus 101 as shown in FIG. 13 with high image qualityof the photographed portions.

In a case where a display screen of a transmission originator includingimage data such as photographs is remotely displayed on a transmissiondestination device, compressed image data of the image portion such asphotographs stored in the storage unit of the transmission originatorcan be transmitted to the transmission destination device, and the imageof the photograph portion can be displayed remotely on the screen of thetransmission destination device with high image quality.

According to the present embodiment, it is possible to display an image,which is displayed on a display unit of a portable device, on a displayunit of an apparatus connected to the portable device through a networkwith high image quality.

Other Embodiment

The object of the present invention can also be achieved by providing astorage medium, storing program codes of software realizing theabove-described functions of the embodiment, to a computer system orapparatus. Further it can also be achieved by reading the program codes,by a computer (CPU or MPU) of the system or apparatus, from the storagemedium and executing the program.

In this case, the program codes read from the storage medium realize thefunctions according to the embodiment, and the storage medium storingthe program codes constitutes the invention.

The storage medium, such as a flexible disk, a hard disk, an opticaldisk, a magneto-optical disk, CD-ROM, CD-R, a non-volatile memory card,and ROM can be used for providing the program codes.

Furthermore, aforesaid functions according to the above embodiment arerealized by executing the program codes which are read by a computer.The present invention includes a case where an OS (operating system) orthe like working on the computer performs part or the entire processesin accordance with designations of the program codes and realizes theabove embodiment.

While the present invention has been described with reference toexemplary embodiments, it is to be understood that the invention is notlimited to the disclosed exemplary embodiments. The scope of thefollowing claims is to be accorded the broadest interpretation so as toencompass all such modifications and equivalent structures andfunctions.

This application claims the benefit of Japanese Patent Application No.2005-241558 filed on Aug. 23, 2005, which is hereby incorporated byreference herein in its entirety.

1. An image data transmission apparatus that transmits image datacorresponding to a display of a display unit to a device connected tosaid apparatus through a network for having the device display thedisplay of the display unit, comprising: a transmission data generationunit that generates transmission data including image data correspondingto the display of the display unit and attribute information of theimage data; and a transmission control unit that transmits thetransmission data generated by said transmission data generation unit tothe device connected to said apparatus through the network.
 2. The imagedata transmission apparatus according to claim 1, wherein in a casewhere the display of the display unit is based on a plurality of imagedata, said transmission data generation unit adds attribute information,indicating that the transmission data is in a XOP (XML-binaryOptimization Packaging) format, to a header of the transmission data. 3.The image data transmission apparatus according to claim 1, wherein in acase where the display of the display unit is based on a plurality ofimage data, said transmission data generation unit generates thetransmission data based on rendering data and each image data, saidrendering data including layout information for specifying on thedisplay unit a display position and size of the display based on eachimage data, and reference information for specifying each image data. 4.An image data transmission method of transmitting image datacorresponding to a display of a display unit to a device connectedthrough a network for having the device display the display of thedisplay unit, comprising: a transmission data generation step ofgenerating transmission data including image data corresponding to thedisplay of the display unit and attribute information of the image data;and a transmission control step of transmitting the transmission datagenerated in said transmission data generation step to the deviceconnected through the network.
 5. The image data transmission methodaccording to claim 4, wherein in a case where the display of the displayunit is based on a plurality of image data, in said transmission datageneration step, attribute information, indicating that the transmissiondata is in a XOP (XML-binary Optimization Packaging) format, is added toa header of the transmission data.
 6. The image data transmission methodaccording to claim 4, wherein in a case where the display of the displayunit is based on a plurality of image data, in said transmission datageneration step, the transmission data is generated based on renderingdata and each image data, said rendering data including layoutinformation for specifying on the display unit a display position andsize of the display based on each image data, and reference informationfor specifying each image data.
 7. A remote display control apparatusthat adapts a display of a display unit of a first device to a displayformat of a display unit of a second device connected to the firstdevice through a network for having the second device performdisplaying, comprising: an analysis unit that analyzes an attribute oftransmission data including image data, which is transmitted from thefirst device; an image data generation unit that generates image dataadapted to the display format of the display unit of the second devicebased on the image data in accordance with an analysis result of saidanalysis unit; and a display control unit that have the display unit ofthe second device perform displaying based on the image data generatedby said image data generation unit.
 8. The remote display controlapparatus according to claim 7, wherein in a case where the analysis ofsaid analysis unit finds that the transmission data is in a XOP(XML-binary Optimization Packaging) format, said image data generationunit obtains a scaling factor necessary to display the image dataincluded in the transmission data on the display unit of the seconddevice, based on the display format of the display unit of the seconddevice.
 9. The remote display control apparatus according to claim 8,wherein in a case where the analysis of said analysis unit finds thatthe transmission data is in a XOP (XML-binary Optimization Packaging)format, the transmission data includes a plurality of image data andrendering data that includes layout information for specifying on thedisplay unit of the first device a display position and size of thedisplay based on each image data, and reference information forspecifying each image data, and said image data generation unit rewritesthe rendering data based on the scaling factor.
 10. The remote displaycontrol apparatus according to claim 8, wherein said image datageneration unit generates image data adapted to the display format ofthe display unit of the second device based on the rewritten renderingdata and each image data.
 11. A control method of a remote displaycontrol apparatus that adapts a display of a display unit of a firstdevice to a display format of a display unit of a second deviceconnected to the first device through a network for having the seconddevice perform displaying, comprising: an analysis step of analyzing anattribute of transmission data including image data, which istransmitted from the first device; an image data generation step ofgenerating image data adapted to the display format of the display unitof the second device based on the image data in accordance with ananalysis result of said analysis step; and a display control step ofhaving the display unit of the second device perform displaying based onthe image data generated in said image data generation step.
 12. Thecontrol method of a remote display control apparatus according to claim11, wherein in a case where the analysis of said analysis step findsthat the transmission data is in a XOP (XML-binary OptimizationPackaging) format, said image data generation step obtains a scalingfactor necessary to display the image data included in the transmissiondata on the display unit of the second device, based on the displayformat of the display unit of the second device.
 13. The control methodof a remote display control apparatus according to claim 11, wherein ina case where the analysis of said analysis step finds that thetransmission data is in a XOP (XML-binary Optimization Packaging)format, the transmission data includes a plurality of image data andrendering data that includes layout information for specifying on thedisplay unit of the first device a display position and size of thedisplay based on each image data, and reference information forspecifying each image data, and in said image data generation step therendering data is rewritten based on the scaling factor.
 14. The controlmethod of a remote display control apparatus according to claim 11,wherein in said image data generation step, image data adapted to thedisplay format of the display unit of the second device is generatedbased on the rewritten rendering data and each image data.
 15. Atelevision apparatus having the remote display control apparatusdescribed in claim
 7. 16. A television system comprising: the image datatransmission apparatus described in claim 1; and the televisionapparatus described in claim 15, which is connected to said image datatransmission apparatus through a network.
 17. A program that is storedin a computer-readable storage medium and causes a computer to executethe image data transmission method described in claim
 4. 18. A programthat is stored in a computer-readable storage medium and causes acomputer to execute the control method of a remote display controlapparatus described in claim
 11. 19. A computer-readable storage mediumstoring the program described in claim
 17. 20. A computer-readablestorage medium storing the program described in claim 18.